VOL. XXIII. No. 8.] 



POPULAR SCIENCE NEWS. 



125 



QJ-IESTIONS AND ANSWERS. 



Letters of inquiry should enclose a two-cent 

 stump, as well as the name and address of the wri- 

 ter, which will not be published. 



Questions regarding the treatment of diseases 

 cannot be answered in this column. 



Subscriber, 111. — Is there any more powerful 

 explosive known than nitro-glycerine.' 



Ansieer. — Chloride of nitrogen explodes much 

 more violently, but is so very dangerous and unsta- 

 ble that it is of no practical use. A ray of sunlight 

 is sufficient to produce a violent explosion. 



C, Mass. — I have been trying to make some crys- 

 tals of cupric nitrate, Cu (N03)2, but cannot suc- 

 ceed in doing so. What is the matter.' 



Answer. — Cupric nitrate is a deliquescent salt, and 

 rapidly absorbs moisture from the air. It is also 

 decomposed at a temperature of 149' F. into a basic 

 salt, Cu (NO.i)2. 3Cu (HO)2. Try dissolving the 

 metal in the acid till the acid is all neutralized, and 

 evaporate as much as possible, at a temperature 

 lower than that given above. When the crystals 

 are formed they should be removed carefully, 

 quickly dried on blotting-paper, and transferred to 

 a glass-stoppered bottle. 



M. D. writes that an attempt to clean the hair and 

 scalp with the yolk of an egg, as recommended in a 

 recent issue of this paper, will only lead to disap- 

 pointment and profanity. The white of the egg is 

 the proper part to use. 



Si'BsCRiBER, Texas. — What was the composition 

 ol the "malleable glass" known to the ancients.' 



Answer. — No such substance as malleable glass is 

 known at present, and it is not likely that it was 

 really ever produced in former times. It is impos- 

 sible to render any substance of a vitreous nature 

 soft and malleable, and it is most probable that the 

 ancient writers either recorded some wonderful 

 "yarn" of their day, or were deceived by a clever 

 imposter. 



Student, Boston. — Will the year 1900 be a leap- 

 year? and if not. why? 



Ans.ner. — 1900 will not be a leap-year, because the 

 length of the year is not exactly 365V4 days. It is 

 really a little less (iini. 146.). and, as the difference 

 keeps increasing from year to year, it is necessary 

 to drop out the extra day every hundred years or so, 

 to bring the calendar right. Even this correction is 

 not quite exact, but it will serve for a great manv 

 centuries, so there is no pressing need of reform. 



LITERARY NOTES. 



Electrical Rules, Tables, Tests, and Formula, bv 

 Andrew Jamieson, C. E. Industrial Publication 

 Co., New York. 



The great development of the practical uses of 

 electricity within the past few years, has led to a 

 large increase in number of those who are con- 

 stantly employed in the erection and maintenance 

 of electric circuits for various purposes. To all 

 such this little book will be of great value, as it 

 gives all the necessary directions and formula; for 

 such electrical tests and measurements as must con- 

 stantly be made. Many of the methods described 

 are new, and more convenient and accurate than 

 those formerly used. 



Messrs. D. C. Heath & Co. have published a 

 cheap edition of Daudet's delightful story of La 

 Jielle Nivernaise, especially prepared for the use of 

 students of French. The copious notes render all 

 necessary aid to the translator, and the high literary 

 merit of the story is an added attraction. 



Pamphlets, etc., received: Home Rule and Fed- 

 eration, E. Truelove, London: The Relationship 

 Between Human and Bovine Tuberculosis, by E. F. 

 j3rush, M. D. ; Blindness and the Blind, by L. 

 Webster Fox. M. D. ; The Tail of the Earth, by 

 William Danmar; Report of the -Jacksonville Yellow 

 Fever Epidemic of 1888; Observations Upon the 

 Osteology of the American Anseres, bv R. W. Shu- 

 feldt, M. D., Smithsonian Institution ; The Natural 

 History of the American Oyster, by Dr. A. Oelniar, 

 Savannah, Ga. ; The Efficacy of Filters, and Other 

 Means Employed to I'urify Drinking Water, by 

 Charles G. Currier, M. D., New York; Sixty-fifth 

 Annual Report of the Hartford (Conn.) Retreat for 

 the Insane, and the Bulletins of the Iowa and Kansas 

 Agricultural Experiment Stations. 



MODERN DISEASES. 



With the general advance of medical 

 science, there has been, apparently, in mod- 

 ern times, a host of new diseases developed 

 with which our ancestors were unacquainted. 

 The proprietors of the various cin-e-all nos- 

 trums, make the most of them in their sensa- 

 tional advertisements, pointing out the alleged 

 terrible nature of the diseases caused by our 

 modern habits of living, and the impossibility 

 of escaping from them, except by the aid of 

 their infallible "cures." 



It is a fact beyond dispute that the man of 

 the present dav is stiongcr, healthier, and less 

 liable to attacks of disease, than in any pre- 

 ceding age. There are no more real diseases 

 than there were a himdred years ago, but, 

 with oiu" increasing knowledge, we are able 

 to observe differences not then noted, and to 

 seperate into di.stinct diseases, each requiring 

 diflerent treatment, certain affections which 

 were formerly grouped together under one 

 general name. Pneumonia, for instance, was 

 rarely heard of in former times, but "lung 

 fever" was none the less fatal, and even more 

 to be dreaded in the absence of any rational 

 method of treatment. Before the general use 

 of the microscope and chemical reagents for 

 testing the urine, diabetes, Rright's disease, 

 and many others were not thoroughly differ- 

 entiated, but were called by the general name 

 of kidney trouble, and were ju,st as common 

 as in these modern times when ".safe" and 

 infallible cires are advertised for sale at every 

 drug store. The forms of brain disea.se ac- 

 companied by paralysis were in existence 

 long before the term paresis was introduced 

 into the medical vocabulary, and the victim 

 of alcoholic dementia is not favored with the 

 sight of any more zoological curiosities than 

 his predecessor who merely had the common 

 jim-jams. 



"Heart failure" is the latest term of this 

 sort employed to indicate the cause of death, 

 and is a most imfortunate one. It really has 

 no meaning at all, for the failure of the heart 

 to do its work always occurs at the end of 

 life. It may be said that death is always 

 caused by the failure of either the heart or 

 lungs to perform their duties, and that the 

 various forms of accidents or disease are only 

 indirect causes, inducing such failure. 

 Heart failure is not a disease, but the result 

 of disease, and there is nothing new about it 

 whatever. When applied to organic or func- 

 tional diseases of the heart it may have some 

 significance, but such a general term had best 

 be used only in a very general sense. 



Notwithstanding the wails of the pessimists 

 mankind are steadily improving in bodily 

 strength and vigor. Even the immense con- 

 sumption of patent medicines fails to stop the 

 improvement — a fact which goes to prove 



the general absence of any medicinal qualities 

 whatever, in these preparations. The average 

 length of life is greater, and the standard of 

 bodily health higher than ever before, and, if 

 it were not that medical and sanitary skill 

 now preserves for a life of imperfect health, 

 many weak persons who in former times 

 would have succumbed to the first attack of 

 disease, the standard would be even higher. 

 In the works of old writers there are many 

 passages which show that a man was con- 

 sidered old and past his prime at forty, while 

 now at that age one is in the very height of 

 his powers. There may be more diseases 

 now than formerly, but there is less disease, 

 and a vastly greater knowledge of how to 

 avoid it, or, when attacked, to bring it to a 

 favorable termination. 



. . INDIAN REMEDIES. 



A LARGE, and particularly ignorant class 

 of quacks advertise themselves as "Indian" 

 doctors, and claim to have learned secrets of 

 the healing art from the aboriginal inhabitants 

 of this country, and to be able to effect cures 

 by means of remedies obtained IVom roots 

 and herbs "where all others fail." 



Without enlarging upon the falsity of the idea 

 that vegetable remedies are always harmless, 

 we would say that the Indians have no par- 

 ticular medical skill, but, like other savage 

 tribes, depend principally upon incantations 

 and magic to drive off disease. The Indian 

 medicine-men do not employ medicine, as 

 we understand it, at all, but trust for their 

 reputation, to their power to work upon the 

 superstitious fears of their ignorant followers. 

 In this respect the modern Indian doctor is 

 about on a par with his savage colleague. 



The subject of the Indian pharmacopdna 

 has been investigated by several competent 

 persons, and they have found that the 

 remedies used by them are of the simplest 

 kinds, and that none of them are particularly 

 novel or superior to those already in use by 

 the white men. Common sense would in- 

 dicate that a people so far behind in all other 

 arts and sciences of civilization, could not 

 have attained any great superiority in a 

 science like that of medicine which employs 

 the highest powers of the intellect. But the 

 unknown is always great, and a certain 

 number' of people will continue to place their 

 trust in doctors of the Indian, Chinese, Negro, 

 and other semi-civilized races, to say nothing 

 of the mind-healers, and similar products of 

 more enlightened nations. 



Sam Jones on the Faith Cure. — "I'll tell you 

 where this faith cure comes in. There's an old brother 

 and sister, who have been taking all the nasty, quack, 

 patent medicines on the market for the last ten 

 years. Somebody comes along and prays over 'em, 

 and they quit using the patent medicines, and they 

 are well again. They say it was faith that cured. 

 It was faith. It was the faith which caused them to 

 quit taking old patent nostrums, which cured them." 



